I promise I am in this for the long haul.

我保证我会坚持到底。

《牛津词典》

I promise I will send you an email to explain all of these tomorrow.

我保证明天会给你发邮件解释这些问题。

youdao

I promise I won't do anything stupid.

我保证不会做任何愚蠢的事。

youdao

"Johnsy,dear," said Sue, "will you promise me to keep your eyes closed, and not look out the window until I am done working?

VOA: special.2009.08.01

I promise I'll pay you back tomorrow.

我保证明天就还你。

I didn't 实战 - SpeakingMax英语口语达人

There's in those images, I think, a kind of utopian promise that the familiar, ordinary pleasures of rural life can be recaptured in a new society of plenty.

在这些图片中，我认为有一种乌托邦的希望,对乡村生活熟悉而平凡的快乐的希望,能在一个自足的新社会里重新得到快乐的希望。

耶鲁公开课 - 现代诗歌课程节选

"I promise I'll find a way to avoid cuts to frontline policing, " added Mr Savage.

BBC: John Savage

Do so and I promise I'll Tivo Mad Men one Sunday night and enjoy a night at the movies.

FORBES

So I promise I will keep you guys updated as time goes on.

WHITEHOUSE: President Obama on Deficit Reduction